function setPosition(popWidth, popHeight){
  //alert('Your resolution is '+screen.width+'x'+screen.height);
  tmp=(screen.availWidth/2)-popWidth/2; 
  tmpStr=tmp+"px"

  tmpH=(screen.availHeight/2)-(popHeight/2)-130;  //130px to jest w przyblizeniu elementy menu przegladarki
  tmpHStr=tmpH+"px"

  document.getElementById('popup').style.left=tmpStr;
  document.getElementById('popup').style.top=tmpHStr;
}

function closePopUp(){
  document.getElementById('popup').style.visibility="hidden";
}